Magnus the Red

Magnus the Red is the one-eyed primarch of the Thousand Sons, a sorcerer who broke the Webway trying to warn the Emperor. He thought knowledge was a kindness. Terra learned it as a wound.

Russ burned Prospero under that warning. Magnus gave himself to Tzeentch to save what was left of his sons, then spent the Heresy learning that salvation from the Changer always costs a second price. Sortiarius is his world now, not the libraries of Tizca.

He still argues with Ahriman, still hates the Wolves, and still wants his father to admit the warning was true. The Crimson King has time. The Imperium does not.